Pipe-bending machine.



' PATENTED AU'GM, 1903.

w. R?. SMITH. PIPE BENDING MACHINE.

Arrmouon PILBnooTJza. 1902.

no MODEL;

1u: Noms UNITED STATES d WILLIAM :Patented August 4, 1903.

EEICE.

n.3 SMITH, on EoSToN, MASSACHUSETTS, ASSIGNoR or ONE-HALE To E. A. HOUDLETTE, or BOSTON, MASSACHUSETTS.

Pmi-:d -EENDINe MACHINE.

SPECIFICATION forming part ef Letters Patent No.. 735,307, dated `August 4, 1903.

' Application iiled October 23, `1902. Serial No. 128,467. (No model) T0 all whom/'it may concern.- i i Be it known that LWILLIAM R. SMrTH,\of

Boston, in the countyof Suffolk and State of Massachusetts,have invented certain new and useful Improvements in Pipe-Bending Machines, of which the following is a specification.

This invention relates to appliances or machines for bending pipes, and has particular reference to that type of such devices which are employedY for bending short lengths of pipe. i A l While the invention in the embodiment shown in thedrawings is adapted particularly for hand use, so that it might be termed a tool or appliance, yet it is capable, as will be readily. understood hereinafter, of beingA embodied in a machineso that the moving parts may be driven by power.

One object of the invention is to provide an improved construction of bending-rolls` `made. V

. A further object is to provide means for holding the pipe, which means may also constitute a `passage for the supplyfof steam or other duid or material for filling the pipe and warming it and for resisting compressive pres-A sure during the bending operation. Y,

the construction and arrangement of parts, substantially as hereinafter claimed. Y, A y d Of the accompanying drawings, Figure 1 represents aside elevation, partly in section,

representing theinvention in one of the forms taken through the pipe-holder and nipple and connections. Fig. 5`represents a modiiicationhereinafter described.

described and The same reference characters indicate the same parts in all the figures. l

In the embodiment of the invention illustrated in the drawings a suitable standard, upright, or beam is represented at a', to which is secured a plate b, having bracket-armsb', supporting the pivot c' of a lever c. ver c carries the upper'bending-roll d, and a lower bending-roll d is mounted on the pivot c of the lever.A y i A pipe e extends through the plate b and standard ct in alinement with the opening between the two rolls when the lever c is in upright position. Behind the upright "ay `said pipe e is connected to a pipefby means of a coupling e. Said pipe fis to beconnected' to a suitable source of steam or of otherfluidor materialadapted to be forced into the pipe to be bent, as hereinafter described. The front end of thepipe e is formed externally with a screw-thread, which is preferably a left-hand thread, and tted thereto is a sleeve g, which is internally threaded at its inner end to iit the threads of the projecting portion of the pipe e, and which sleeve is at its outer end formed with an internal thread to fitthe usual right-hand thread formed on the end of the pipe to be bent. The sleeve g, carried lby the pipe'e, constitutes a socket for the pipe to be bentand at the same time constitutes a nipple throughwhich the hot Huid or other material referred to may be forced into said pipe. If no steam or other fluid or equivalent thereof is to be forced into the pipe to be bent, the

\ parts c and g may be a simple socket; To these ends the invention consists in` In the use of this device a pipe fr' is inserted between the rolls in the position indicated by full'lin'esin Fig. 1, the outer end of said Vpipe being provided with a cap `is screwed into the socket ofthe sleeve g, and then the heating medium is introduced through the pipe e, if such medium is to be employed, the pipe x' serving to preventthe escape of such medium. The lever c is then turned toward the position represented by the dotted lines in Fig. 1, causing the roll d to bend the pipe a; over the periphery of the roll d. 'Ihis operation of bending is well known, with the exception of the heating medium. By the employment of the heating Said pipe Said le- IOO is afforded for the pipe while being bent.

medium I am able to facilitate the bending of the pipe, and also, if such medium' is under sufficient pressure, an internal support It will thus be seen that the pipe e and sleeve g constitute a combined pipe-holder and supply-nipple.

As clearly shown in Fig. 3, the groovesv of the rolls are not semicircular in cross-section. Instead they are semi-elliptical, so that the opening between the contacting portions of the two rolls will form a true ellipse. This prevents the fiattening of the pipe during the bending operation. I have found in practice that when two rolls are employed having grooves of such shape that the passage between the contacting points of the rolls is a true circle the operation of bending the pipe results in flattening it. This isdue to the fact that the outer side of the pipe is.

stretched, while the inner side is contracted. The pipe will retain a diameter equal to the width of the passage-way in a plane parallel with the axis of the rolls, but will be flattened iu a direction at a right angle to the axes of the rolls. By giving a semi-elliptical form -to the grooves I prevent an undue compressing action upon the outer surface of the curve of the pipe as it is being bent, while the width of the opening between the two rolls is designed to be such that the said opening will closely receive the pipe. In other words, the external diameter of the pipe to be bent should be practically the same or but very slightly smaller than the shortest-diameter of theopening or passage between the rolls.

In order to provide an adjustment whereby the width of the grooves in the rolls may be varied, I make said rolls in two parts, as clearly shown in Figs. 3 and 5. As shown in Fig. 3, I interpose between these parts spacing-disks or circular plates h, which may be, as here shown, perfectly fiat. By varying the thickness of the interposed spacing-plates I Vary the width of the groove. In Fig. 5 I show a spacing disk or plate h which is fluted, so that it will yield to some extent upon screwing up the bolts which connect the two halves of the roll.

I claim-l l. Apipe-bendingmachinecomprisingcontacting rolls, one of which is movable about the axis of the other, said rolls having semielliptical grooves in their peripheries, adapted to conjointly form an elliptical passage for pipe to be bent, each of said rolls comprising two parts bolted together and adapted to receive spacing-plates between them.

2. A pipe-bending machine comprising a pair of rolls, one of which is movable about the axis of the other, the said rolls comprising two parts bolted together and adapted to receive spacing-plates between them.

3. A pipe-bending machine comprisinga lever having a grooved roll, another grooved roll having its axis coincident with the pivot of the lever, and a combined pipe-holder and supply-nipple in alinement with the opening between the two rolls when the lever is in inoperative position, said pipe-holder and supply-nipple being connected with a rigid support.

4. A pipe-bending machine comprising a plate having a bracket, a suitable support for said plate, a grooved roll mounted in said bracket, a lever mounted to vibrate on a pivot WILLIAM R. SMITH.

Witnesses:

C. F. BROWN, E. BATCHELDER. 

